1. Field of the Invention
The invention relates to a copper foil and a method of manufacturing the copper foil.
2. Description of the Related Art
In case of bare copper foils, the surface is subjected to a reddish brown to black discoloration over time due to oxidation, whereby the appearance deteriorates. In case of copper foils of Sn-plated copper, the surface is grey in color and therefore the appearance is not good.
Thus, an oxidation-resistant copper foil is needed which can maintain the excellent appearance or color of copper-based metal materials.
A method for improving the corrosion resistance of copper or copper alloy members is known in which zinc (Zn) is plated on a surface of copper material and is subsequently diffused by heat treatment to form a copper-zinc (Cu—Zn) layer with a zinc (Zn) concentration of 10 to 40% (see JP-A-S62-040361).
Another method is known in which a layer of nickel (Ni), etc., is formed on a surface of a copper-based member by plating.
In recent years, it was reported that amorphous alloys exhibit excellent corrosion resistance due to the structure in which atoms are densely packed (see WO2007/108496, JP-A-2008-045203, JP-A-2004-176082, JP-A-2001-059198 and JP-A-2010-163641).